The present invention relates to solid-gas-liquid reaction apparatus which permits both gas liquid contact process and solid precipitation simultaneously in a single reaction vessel.
There are known various simultaneous methods of making a gas-liquid contact and solid precipitation possible. One is known as a flue gas desulfurizing process which consists of processing flue gas from boilers, etc. in an aqueous solution containing an alkali or acid and eliminating SO.sub.2 from the flue gas by absorption. Another is a method of producing ammonium sulfate by processing a content of ammonia gas in a gas from a coke furnace by employing a medium of sulfuric acid. A third is a method of manufacturing hydroxylamine in which nitrogen oxide produced by oxidizing ammonia with air is absorbed by water, and is reacted with ammonium sulfite. A fourth is the ammonia-soda process of manufacturing soda ash. When large quantities of gas are processed in the above conventional methods, the gas-liquid contact reaction apparatus used includes a tower in which countercurrents of gas and liquid are brought in contact, a packed column, a plate column, a spray column, etc. The solid precipitation apparatus used includes various types depending on the purpose, and because of the necessity of suspending solids, all types employ a barrel-type vessel having a stirrer therein. For large quantities of gas continuously to be processed by placing the gas in contact with a liquid and by obtaining solids by precipitation, it is usual that the gas-liquid contact apparatus and the precipitating apparatus are provided independently or separately because of their different functions and constructions, and are connected by pump and piping system.
The present inventors have studied possibilities of combining the two different apparatus into a single unit and it has been revealed that combining the two units physically or simply will only make a large apparatus and will thus not have the benefit of the combination. It has been observed that a solution to the above problem can be provided by a new process of making contact between a gas and liquid in the presence of a solid.